September 2005 Archives - Transmission Digest
Procrastination – Should We Talk About It Now or Wait Awhile?

When people attend seminars, listen to tapes or read informative books, they tend to get all jazzed up about fixing the problems with their businesses. Unfortunately, if they don’t take action to begin the change soon after the initial impact of recognizing the need and devising a plan to make it happen, the intensity can dwindle quickly or other factors can creep in and stop a good plan dead in its tracks.

Deceived

One step many technicians take in diagnosing transmissions that have electronically controlled line-rise problems is to unplug the pressure-control solenoid. If the solenoid, pressure-regulator valve and pump are in good working order, line pressure will rise to about 150 to 170 psi at 1,000 rpm in Park. If it rose to only 80-90 psi or didn’t rise at all, this would indicate that a problem existed inside the transmission.

Out of Sight, Out of Mind

From time to time the ATSG tech line receives calls concerning 4L80-E transmissions with a reverse and/or third-gear problem. First thought may be compromised piston seals in the direct-clutch drum, or center-support rings. Perhaps even the center-support feed bolt is loose or cracked.

Look Before You Leap (into a CD4E)

How many times has your mother told you to look before you leap? It was good advice when you were a kid, and it’s even better advice if you’re about to tear apart a modern transmission – especially when the transmission in question is a CD4E.

September 2005 Issue

In This Issue
RE4FO4A/V: Harsh Shifting, Code P0745: Nissan Altima, Maxima, Quest; Infiniti G20, I30 Series; Mercury Villager

NV246: Understanding the Tricks

The New Venture 246 transfer case has been around since the 1998 model year. Found in GM K trucks (Tahoe, pickup, Yukon, Suburban, Suburban EXT, Escalade and Avalanche), this is a large, heavy-duty transfer case.

740/1740 Codes and Chrysler Converter Flow

740/1740 codes tell you there is excessive slip at the TCC clutch. The engine and transmission output speeds are constantly being monitored. You can compare the difference in the two speed rates to determine transmission slip. If the RPM parameters for a slip in a given gear are met and TCC apply has not been commanded, you will see a gear-ratio code. But, if the RPM parameters for a slip in a given gear are met and TCC apply has been commanded, you will see a (TCC slip) 740 code.